At least some example embodiments of the inventive concepts relate to semiconductor memories and, more particularly, to a memory controller and a method of reading data from a nonvolatile memory by the memory controller.
Semiconductor memory device are memory devices implemented using semiconductors such as silicon (Si), germanium (Ge), gallium arsenide (GaAs), and indium phosphide (InP). In general, semiconductor memory devices are classified into volatile memory devices and nonvolatile memory devices.
Volatile memory devices lose their stored data when their power supplies are interrupted. Volatile memory devices include a static RAM (SRAM), a dynamic RAM (DRAM), a synchronous DRAM (SDRAM), and the like. Nonvolatile memory devices retain their stored data even when their power supplies are interrupted. Nonvolatile memory devices include a read only memory (ROM), a programmable ROM (PROM), an electrically programmable ROM (EPROM), an electrically erasable and programmable ROM (EEPROM), a flash memory, a phase-change RAM (PRAM), a resistive RAM (RRAM), a ferroelectric RAM (FRAM), and the like.
A semiconductor memory is used together with a memory controller. The memory controller is a semiconductor circuit configured to control the overall operation such as a read operation and a write operation of the semiconductor memory. The memory controller uses a random access memory as a working memory to control the semiconductor memory.
For many devices, a size (i.e., capacity) of a working memory used by a memory controller is closely connected to the manufacturing cost of the working memory. The greater the size of the working memory, the more the manufacturing cost of the working memory. The smaller the size of the working memory, the less the manufacturing cost of the working memory. In addition, for many devices, the size of the working memory is closely connected to operating performance of the memory controller. The greater the size of the working memory, the higher the operating performance of the memory controller. The smaller the size of the working memory, the lower the operating performance of the memory controller.